The present invention relates to safety systems for use with automated barrier movement arrangements.
Modern barrier movement systems, such as garage door controllers, generally comprises a motor which responds to move the barrier in preprogrammed ways in response to stimuli. The program is constructed to handle the normal situations relating to the barrier and its movement. For example, when a barrier has been stopped in mid-travel while moving in an opening direction, a subsequent command from a user may cause the barrier to move in a direction toward closing. Also, when a barrier is stopped in mid-travel while moving in a closing direction a subsequent user command may cause the barrier to move toward the open position. Other systems may be programmed to move the barrier toward the closed position when the door has been stopped in mid-travel and a user command is received, regardless of the direction of travel prior to stopping the door.
It may be desirable to always move a barrier stopped in mid-travel in the opening direction. In the case of a vertically moving garage door this results in moving the door upwardly. If all door system, regardless of manufacturer, respond in the same manner it is believed that users may more accurately predict motion of the barrier. In some cases, however, opening (upward) movement of a garage door might create problems. For example, when an upwardly moving door stops because of contact with the bumper or trailer hitch of a car, restarting the door in the upward direction does not solve the problem. Downward door movement would be desired in such situations and if such is denied by the previously mentioned attempt to standardize the direction of travel to always up, then the user may be forced to try to physically disengage the bumper and door. A need exists for an improved arrangement for starting a stopped barrier in an opening direction, but which avoids the above problem.
The need is met and a technical advance is achieved in accordance with the present invention. When a barrier move command is received and the barrier was previously stopped between open and closed positions, the barrier will be moved toward the open position unless predetermined conditions are met. In accordance with an embodiment, a controller responds to a movement command by moving the barrier toward the open position unless the movement command occurs within a predetermined period of time after movement of the barrier was stopped. When the stop was performed in less than the predetermined period of time, previously, another barrier movement algorithm is performed. Such other algorithm may for example be to always move the barrier to the closed position or to move the barrier in a direction opposite to the direction in which it was moving when the stop occurred.
The performance of the other algorithm may depend on further conditions such as the direction of prior barrier travel and/or the cause of stopping the barrier movement. For example, closing movement of the barrier may be enabled only when the movement command is received within the predetermined period of time, the barrier was moving in the opening direction and the barrier is stopped because of a detected obstruction.
The predetermined period of time may be selected to be relatively short so that the performance of the other algorithm occurs only if the movement command is received within approximately 5 seconds to 5 minutes after stopping the barrier. Further, the performance of the other algorithm may depend on the source of the movement command. For example, the other algorithm may be performed only when the movement command originated from a fixed sender such as a wall mounted barrier controller.